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DSLR imaging: Comet Encke, Owl Nebula, Galaxies

Posted: 21 February 2017

Thursday, 16 February 2017, dawned clear, but clouds from the next storm system began arriving mid-day. Occasional light rain arrived on Saturday, 18 February, through Monday morning, 20 February (total 0.23"). The sky cleared shortly after sunrise (as forecast) on Monday, but clouds returned by mid-morning, becoming mostly cloudy by early afternoon (not forecast). Fortunately, the forecast clear sky began returning late in the afternoon.

Open: Monday, 20 February 2017, 1809 MST
Temperature: 74°F
Session: 1074
Conditions: Clear

Equipment Used:
12" f/8 LX600 w/StarLock
Wired AutoStar II handset
2" 24mm UWA eyepiece

D7200 DSLR

1814 MST: sunset. LX600 ON, StarLock OFF, High Precision OFF.

Viewed the planet Venus, 102X. Nice crescent.

I then began setting up the iOptron SkyTracker Pro with the D7200 DSLR:


I would use this set up to try to photograph faint Comet 2P/Encke, low in the western sky after dark.

1830 MST: viewed Venus using the Vortex 12x50 binoculars. The planet's crescent phase was visible in the binoculars. Nice.

1847 MST: using the iOptron iOS app on my iPhone I polar aligned the SkyTracker Pro and did a couple of test exposures of the western sky. Then began waiting for the end of Astronomical Twilight (1936 MST).

1921 MST: with the assistance of SkySafari 5 Pro on my iPhone I located Comet Encke using the 12x50 binoculars. It was small and very faint. No tail was visible.

1927 MST: checked the polar alignment of the SkyTracker Pro since I had done some fiddling with the camera on the mount. 1938 MST: began taking photos of the western sky using the D7200 DSLR on the SkyTracker. This is an f/4.8, 1 minute, ISO 2500, White Balance 4000K, FL 56mm, photo showing Mars, Venus, and Comet 2P/Encke:

Mouseover or tap on image
Mouseover or tap on image for labels

Use the labels in the rollover image to locate the faint comet!

This is an f/5, 1 minute, ISO 2500, WB 4000K, FL 70mm, photo. The inset is a portion of a FL 140mm photo (slightly trailed).


1950 MST: ended comet imaging. The Zodiacal Light was very bright this evening.

1952 MST: last look at Venus, 102X.

I then checked for shadows cast by the planet Venus inside the observatory. I was able to see a faint shadow of a pen held next to the dome. I tried to photograph a shadow of the telescope on the dome but was not successful.

2003 MST: my logbook was getting damp. The humidity was 60%.

2009 MST: slewed to M97 (Owl Nebula). It was a nice view at 102X.

Slewed to the star Regulus, mounted the D7200 DSLR at prime focus + focal reducer, focused on the star using the Bahtinov Mask, and locked the 12" primary mirror.

2025 MST: StarLock ON. Began imaging M97 (Owl Nebula). This is a cropped, 5 minute, ISO 6400, WB 4000K, StarLock autoguided, image:

M97 (Owl Nebula)

StarLock autoguiding was pretty good this night, even with the high humidity.

Slewed to M96 (galaxy) and did some images. StarLock autoguiding on M96 (and M95) was not as good as on M97. Both galaxies were a little lower in the sky however. These are cropped, 5 minute, ISO 6400, WB 4000K, StarLock autoguided, images:

M96 (galaxy)

M95 (galaxy)

2108 MST: ended DSO imaging. StarLock OFF. Unmounted the DSLR from the 12" telescope.

2123 MST: viewed M95 (galaxy) and then M96 (galaxy), 102X. Good views. Then viewed M65, M66, and NGC3628 (Sarah's Galaxy), 102X. All three galaxies of the Leo Triplet were visible in the 2" 24mm UWA eyepiece field-of-view. Lovely.

Then began closing up. 2128 MST: LX600 OFF.

Close: Monday, 20 February 2017, 2138 MST
Temperature: 48°F
Session Length: 3h 29m
Conditions: Clear, humidity 68%

Check out the article "Zonies, Part 5: Sky Glow" at the Paris Review. Oracle State Park and I are mentioned.

On my report of 11 February I mentioned that a neighbor was considering a SkyShed POD observatory for his telescope. He has now ordered the POD! So I'll get a chance to help set up another one!!

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